UPDATE:
First of all, the 3/4 hp Red Lion motor is: 'Made in China' (the whole pump is, and boxed there, too), it's ODP, and it's
very quiet compared to the Sta-Rite's 1/2 hp AO Smith. I kinda wish I'd taken SPL readings before and after, but didn't do a 'before'. :duh:
We installed on Monday, so I've had a few days to see how things are going, use-wise. We put gauges on the pump itself and on the tank side, if not placed ideally within the connection pattern. Foot valve seems to be ok, as there was water in the poly input line nearly to its top when we switched over. ~Two quarts of water and one priming was all it took to get the air moved past the filter and pressure/flow going.
50 psi shut-off takes 8-some minutes from 0 psi showing on both gauges, and ~5 1/2 min when the tank drops to 30 to restart. I left the pump wired for 230v and ran 8' or so of 14ga to a 10a double-trip breaker at the panel. If you can't see it, the pressure switch line is re-routed to the back (output) side of the valve vs on the pump housing.

As you can see, I also added a CSV with hopes of setting the output pressure at around 40 psi. The 'procedure' says to adjust while flowing at a 2-3 gpm rate, but I didn't make that effort. I did turn the adjustment screw in while the tank was filling and saw nothing change on either gauge for several turns. At some point the pump's sound got loud as though cavitating. Pump pressure dropped to near zero, while tank pressure stayed. I quickly backed out the screw till the sound quieted and pump pressure returned to ~45, where it always seems to hover when running, plus another full turn out of the screw. AFAIK it's working as I wanted w/o knowing the exact pressure/flow when in use.
At no time is cooling air from the motor more than barely warm to the touch, the cooling slots actually feel about as warm as the back of my other hand, even at the end of the 8 min run if I forget & leave the breaker 'off' after tinkering and draw it all down. Also seems only then that I see (hear) the pump running at all vs at random during the day. During any part of a run cycle the tank-side gauge goes quickly to ~40 or so and hovers, while the pump-side gauge hovers ~45.
My best test so far is filling the washer, ... what we'd used at first to burp air & see flow at startup. I'd guess the fill time will be quite a quite bit shorter, as the flow was gushing vs trickling when the gauges showed ~20 (vs ~10 previously) and I was running on the pump alone. Terramite and the NH are getting muddy on a concrete-pad job next door, and I'll get one home to spray-off today or tomorrow to see if the system keeps up with the garden hose's nozzle.
If I have something wrong with the CSV setting I have no way of knowing. At this point I'm not too concerned, either, as the performance boost I sought is apparent if not fully vetted. One thing is for sure ... I don't have to hear that noisy older pump anymore. btw, I'll find a use for that somewhere.
I appreciate all comments and questions, hope I cleared some up for other TBN-ers, will post back on how the garden hose test works out.

Thanks, all! t o g